var assignOps = map[token.Token]token.Token{
	token.ADD_ASSIGN:     token.ADD,
	token.SUB_ASSIGN:     token.SUB,
	token.MUL_ASSIGN:     token.MUL,
	token.QUO_ASSIGN:     token.QUO,
	token.REM_ASSIGN:     token.REM,
	token.AND_ASSIGN:     token.AND,
	token.OR_ASSIGN:      token.OR,
	token.XOR_ASSIGN:     token.XOR,
	token.SHL_ASSIGN:     token.SHL,
	token.SHR_ASSIGN:     token.SHR,
	token.AND_NOT_ASSIGN: token.AND_NOT,
}

	AND     // &
	OR      // |
	XOR     // ^
	SHL     // <<
	SHR     // >>
	AND_NOT // &^

	ADD_ASSIGN // +=
	SUB_ASSIGN // -=
	MUL_ASSIGN // *=
	QUO_ASSIGN // /=
	REM_ASSIGN // %=

	AND_ASSIGN     // &=
	OR_ASSIGN      // |=
	XOR_ASSIGN     // ^=
	SHL_ASSIGN     // <<=
	SHR_ASSIGN     // >>=
	AND_NOT_ASSIGN // &^=

	LAND  // &&
	LOR   // ||
	ARROW // <-
	INC   // ++
	DEC   // --

		case '!':
			tok = s.switch2(token.NOT, token.NEQ)
		case '&':
			if s.ch == '^' {
				s.next()
				tok = s.switch2(token.AND_NOT, token.AND_NOT_ASSIGN)
			} else {
				tok = s.switch3(token.AND, token.AND_ASSIGN, '&', token.LAND)
			}
		case '|':
			tok = s.switch3(token.OR, token.OR_ASSIGN, '|', token.LOR)
		case '~':
			tok = token.TILDE
		default:
			// next reports unexpected BOMs - don't repeat

	{token.ADD_ASSIGN, "+=", operator},
	{token.SUB_ASSIGN, "-=", operator},
	{token.MUL_ASSIGN, "*=", operator},
	{token.QUO_ASSIGN, "/=", operator},
	{token.REM_ASSIGN, "%=", operator},

	{token.AND_ASSIGN, "&=", operator},
	{token.OR_ASSIGN, "|=", operator},
	{token.XOR_ASSIGN, "^=", operator},
	{token.SHL_ASSIGN, "<<=", operator},
	{token.SHR_ASSIGN, ">>=", operator},
	{token.AND_NOT_ASSIGN, "&^=", operator},

	}

	x := p.parseLhsList()

	switch p.tok {
	case
		token.DEFINE, token.ASSIGN, token.ADD_ASSIGN,
		token.SUB_ASSIGN, token.MUL_ASSIGN, token.QUO_ASSIGN,
		token.REM_ASSIGN, token.AND_ASSIGN, token.OR_ASSIGN,
		token.XOR_ASSIGN, token.SHL_ASSIGN, token.SHR_ASSIGN, token.AND_NOT_ASSIGN:
		// assignment statement
		pos, tok := p.pos, p.tok
		p.next()
		y := p.parseRhsList()

	}

	x := p.parseList(false)

	switch p.tok {
	case
		token.DEFINE, token.ASSIGN, token.ADD_ASSIGN,
		token.SUB_ASSIGN, token.MUL_ASSIGN, token.QUO_ASSIGN,
		token.REM_ASSIGN, token.AND_ASSIGN, token.OR_ASSIGN,
		token.XOR_ASSIGN, token.SHL_ASSIGN, token.SHR_ASSIGN, token.AND_NOT_ASSIGN:
		// assignment statement, possibly part of a range clause
		pos, tok := p.pos, p.tok
		p.next()
		var y []ast.Expr

		{"(Token).IsOperator", Method, 0},
		{"(Token).Precedence", Method, 0},
		{"(Token).String", Method, 0},
		{"ADD", Const, 0},
		{"ADD_ASSIGN", Const, 0},
		{"AND", Const, 0},
		{"AND_ASSIGN", Const, 0},
		{"AND_NOT", Const, 0},
		{"AND_NOT_ASSIGN", Const, 0},
		{"ARROW", Const, 0},
		{"ASSIGN", Const, 0},
		{"BREAK", Const, 0},
		{"CASE", Const, 0},
		{"CHAN", Const, 0},

pkg go/scanner, type Scanner struct
pkg go/scanner, type Scanner struct, ErrorCount int
pkg go/token, const ADD Token
pkg go/token, const ADD_ASSIGN Token
pkg go/token, const AND Token
pkg go/token, const AND_ASSIGN Token
pkg go/token, const AND_NOT Token
pkg go/token, const AND_NOT_ASSIGN Token
pkg go/token, const ARROW Token
pkg go/token, const ASSIGN Token
pkg go/token, const BREAK Token

pkg go/printer, type Config struct, Indent int
pkg go/scanner, const ScanComments = 1
pkg go/token, const ADD = 12
pkg go/token, const ADD_ASSIGN = 23
pkg go/token, const AND = 17
pkg go/token, const AND_ASSIGN = 28
pkg go/token, const AND_NOT = 22
pkg go/token, const AND_NOT_ASSIGN = 33
pkg go/token, const ARROW = 36
pkg go/token, const ASSIGN = 42
pkg go/token, const BREAK = 61
pkg go/token, const CASE = 62